FERMENTS IN SNAKE VENOM 211 
we still have a long way to travel through the most complex and misleading 
paths of study. I propose, therefore, to record only the facts already obtained 
by various investigators up to the present moment. 
PROTEOLYTIC ACTION OF SNAKE VENOM. 
Flexner and Noguchi, with a view to finding a suitable explanation of the 
softening effect of venom upon muscle, described so fully and graphically by 
Mitchell and Reichert, carried out a series of experiments for determining 
whether or not venom contains a proteolytic ferment. As the softening of 
muscle takes place quickly, within 30 minutes to a few hours, the operation 
of bacteria can be excluded. Several proteid substances were exposed to 
venom in sterile saline solutions, prepared by passing the dissolved venom 
through the Chamberland filter. In some experiments the solution was kept 
under a layer of toluol. Gelatin in 10 per cent solution was mixed with 
crotalus and cobra venom in solutions containing 10 mg. of dried venom. 
Cobra venom brought about complete liquefaction in two days, crotalus in 
16 hours. Fibrin heated to coagulation (60° to 62°C.) is not attacked by 
venom; coagulated egg-albumin is also unaffected. On the other hand, raw 
fibrin obtained from dog, rabbit, and guinea-pig is easily and more rapidly 
fragmented by venom than in the control tubes. Venoms heated to 75° C. 
for 30 minutes lose their liquefying property. The addition of Calmette 
antivenin does not influence the result. 
Muscle in thin slices was taken from the pigeon and guinea-pig; 2 per cent 
solution of venom (cobra, crotalus, water-moccasin) was filtered through the 
Chamberland bougie. To one set of tubes the muscle was added; to another 
set, muscle plus the sterile serum of the animal; while in a third the muscle 
minus venom was placed. The control tubes showed no change to the naked 
eye after 6 hours’ contact. The temperature was 36°C. In the other tubes 
changes were noticed in 2 hours. At this period the muscle was opaque, 
swollen, and of a grayish color, and the fibers were separated. In 3 hours the 
swelling and separation of the fibers had increased, and by shaking the tubes 
the slices of muscle could be easily broken up. In 6 hours disintegration was 
complete. 
Crotalus serum is without liquefying action upon gelatin. 
Flexner and Noguchi concluded, therefore, that venom contains a body 
capable of modifying protein, and upon this the softening effect of muscle 
tissue im corpore doubtless depends. 
Delezenne ' has established the existence in venoms of a kinase analogous 
to the kinase of leucocytic origin and to enterokinase. The venom alone 
does not attack the heat-coagulated egg-albumin, but it confers upon the 
inactive pancreatic juice an intense digestive power. The venom of Lachesis 
is shown to be the richest in kinase. It digests gelatin completely and after 
the latter is subjected to the action of this venom it becomes incapable of 
solidification. 

1Delezenne. Sur l’action kinatique des venins. C. R. Ac. des Sc., 1902, CXXXV, 329. 
